Method of treating fur skins and the like



FIF8509 Fifi I Patented May 8, 1928,

UNITED STATES PATENT OFFICE.

HYMAN STEIN, 0F ARVERNE, WILLIA1VI E. AUSTIN, OF NEW YORK, AND IRVINGLIEBO- WITZ, OF BROOKLYN, NEW YORK, ASSIGNORS T0 STEIN FUR DYEING (30.,INCL, OF NEW YORK, N. Y., A. CORPORATION OF NEW YORK.

METHOD OF TREATING FUR SKINS AND THE LIKE.

No Drawing.

Our resent invention relates to methods of bleac ing fur skins and thelike, and aims to devise methods of the general character specifiedwhich are simple to practice, easy, convenient and economical to putinto practice, which require simple, cheap and readily obtainablereagents and apparatus for their practice, and which produce bleachedfur skins and the like possessing superior characteristics for theintended purpose, such bleached fur skins and the like beingcharacterized by the superior strength of the leather and hair portionsof such bleached fur skins and the like, the superior lustre of the hairportions of such bleached fur skins and the like, and the superiorappearance of such bleached fur skins and the like, the strength of theleather and hair portions, and the lustre of the hair portions, of suchbleached fur skins and the like comparing quite favorably with theserespective properties of the fur skins and the like in their natural,unbleached condition.

In the accompanying specification we shall describe an illustrativeembodiment of the process of the present invention, particularly asapplied to the bleaching of fur skins for the production of bleached furskins having the hair and leather portions of the same substantiallyunaffected as to strength, and the lustre of the hair portionssubstantially unimpaired. It is, however, to be clearly understood thatour invention is not limited to the specific embodiment thereof hereindescribed for purposes of illustration only. It is further to beunderstood that our invention is not limited to the treatment of theparticular kind of fur skins or equivalent materials described herein byway of illustration merely, the invention being capable of generalapplication and being adapted for the successful bleaching of otherspecific materials.

While various types and classes of fur skins, for example, may bebleached in accordance with the principles of the present invention, wemay, for example, use brown mouifions as being an example of the classof fur skins to which the principles of the present invention may beapplied with particular success. The brown mouffions may first be washedor killed in an alkaline solution, for example, a solution of sodipmcarbpnate. l his washing operation ordinarily re- .Application filed.October 14-, 1925. Serial No. 62,451.

quires from about two to about three hoursi The washed or killed skinsare then rinsed and thoroughly hydro-extracted. However, the washing orkilling operation may be, omltted, since the subsequent treatment will 5substantially accomplish the same results, to-Z gether with many others,as are accomplished by the washing or killing treatment just described.

We now subject the fur skins or the like, whether or not the same havefirst been washed or killed as above described, and whether the samecomprise brown moufiions or some other material adapted to be treated inaccordance with the principles of the present invention, to the actionof the bleaching agent. Preferably the bleaching agent comprlses hydrogenperoxide. We prefer to use a form ofdiydi dgeri peroxidgfreenfnom acids, particularly mineral acids? since we find that thepresence of such acid or acids, especially when brought into contactwith an alkali or alkaline reagent oraits equivalent, as may happen inthe latter stages of the present process, generates heat and producesmetallic salts, both of which agencies cause a more rapid action of thehydrogen peroxide than is desirable, and often brings about singeing orother harmful oxidation of the hair and 3 leather portions of the furskins and the like being bleached.

While the hydrogen peroxide bleach, for example, may be used of theordinary strength in which such reagent is usually obtainable in themarket, which is in the strength of a 3% solution, we may use thehydrogen peroxide in greater strengths, since by means of the principlesof the present invention a more concentrated hydrogen peroxide may beused without adversely affecting the fur skins and the like beingbleached. For example, we may use a strength of hydrogen peroxidesolution up to 7 or even higher. Preferably we use this reagent instrengths of from about four to about seven per cent, preferably thelatter strength.

T0 the r q earer x desol of the strength or "strengths just designated,we add an alkali or alkaline reage nt. The purpose of this reagiit is toaccelerate the bleaching action but without doing this in a manner whichwill tend to singe or otherwise adversely affect the hair or leatherportions of the fur skins or the like being treated. For this purpose weprefer to employ a solution of annngpia, for example, a concentratedseintruir of ammonia in an amount equal to about to 1 per cent, byvolume, of such a concentrated solution, to a unit volume of thesolution of hydrogen peroxide or other bleach employed.

It may here be stated that the ammonia or its equivalent not only actsin some manner to accelerate the bleaching operation, but withoutadversely affecting the strength of the hair and leather portions andthe lustre of the hair portions of the fur skin and the like beingtreated, but serves also to dissolve, by a sort of saponifying action,fatty bodies and the fatty tissues, as well as some of the othertissues, at the surfaces of the hair portions of the fur skins and thelike being treated. This solvent action serves to prepare the fur skinsand the like for the bleaching action and thus to accelerate such actionwithout any substantially harmful effects.

We also prefer to have present in the bleaching reagent a saponaceousagent, such as a sggp sglution, as a concentratedsolution of a potassiumsoap in an amount equal to from about 1 to about 2 per cent, by volume,of the volume of the bleaching reagent. The presence of the saponaceousbody serves to render the action of the ammonia or equivalent alkalinereagent more mild and serves also to strengthen the hair and leatherportions of the skin being bleached. The saponaceous body serves also inother ways to improve the quality of the final product.

\Vhile the bleaching reagent, containing the hydrogen peroxide, theammonia, and the potassium soap, for example, and pre pared as abovedescribed, may be applied in various ways to the brown moufllons orother materials being treated in accordance with the principles of thepresent invention, we prefer to brush the brown mouffions or other furskin, for example, with the bleaching agent above described. This may bedone with brushes in the usual manner, as will be readily apparent tothose skilled in the art to which the present invention relates. Asuflicient amount of the bleaching reagent above described is applied tothe fur skins or the like being treated, preferably by the brushingaction described above,to cause the desired bleaching action when thebleaching operation is completed, care being taken not to apply more ofthe bleaching reagent than is necessary for this purpose. This is forthe reason that an excess of the bleaching reagent might have harmfuleffects in weakening the hair or leather portions of the fur skins orthe like being treated.

The brushed fur skins and the like are now permitted to dry, preferablyin the pres ence of a gaseous oxidizing medium, such as the air. Thepresence of air seems in some way to facilitate the bleaching action andto yield a final product having the desired bleached and othercharacteristics.

\Ve prefer that the bleaching operation shall be conducted at atemperature of from about (it) to about 100 F. The lower thetemperature, the slower the bleaching operation, and vice versa.However, it is not desirable to raise the temperature too high, sincethis might have a tendency to drive ofi the ammonia and to decompose thehydrogen peroxide too rapidly, which would tend to singe the hairportions and possibly to weaken the hair and leather portions of the furskin being treated.

Since the ammonia or its equivalent acts as a solvent for fattysubstances and for the fatty and other tissues at the exteriors of thehair portions of the fur skin or the like being treated, we prefer notto have too much of this reagent in contact with the leather portions ofthe fur skin, since this would tend to weaken the fibers of such leatherportions.

The advantages of the process are numerous and of great practicalimportance. The process, as illustrated above, is very simple,comprising a few easily practiced steps, and the entire process is easy,convenient and economical to carry out. The process has the furtheradvantages that it requires but simple, cheap and readily obtainablereagents and apparatus for its complete and successful practice.

The results of the process are equally valuable. The product ischaracterized by its very attractive appearance. The hair and leatherportions of the bleached fur skins or the like will be found to havesubstantially their original strength. Similarly, the hair portions ofthe bleached fur skins or the like will be. found to have substantiallythe same lustre as the hair portions of the unbleached skins or thelike. Other advantages of the method of the present invention and thesuperiorities of the resulting product will readily occur to thoseskilled in the art to which the same relates.

What we claim as our invention is:

1. The method of bleaching fur skins and the like, which comprisestreating the same with an aqueous solution of hydrogen peroxide of astrength of more than about 3 per cent, said solution containing ammoniaand a water-soluble soap.

2. The method of bleaching fur skins and the like, which comprisestreating the same with an aqueous solution of hydrogen peroxidecontainingammonia and a water-soluble soap.

3. The method of bleaching fur skins and the like, which comprisesbrushing the same with an aqueous solution of hydrogen peroxide of astrength of more than about 3 per BLEl-RCHENG {it LWEING; FLUEDTREATMENT (it CHEVHOM MODIFI- CAlON OF TEXTILES & FEELRS,

cent, said solution containing ammonia and or the like so treated tobecome dry in the a Water-soluble soap, and thereafter causing presenceof a gaseous oxygen-containing oxithe fur skin or the like so treated tobecome dizing agent. dry in the presence of a gaseous oxygen con- Intestimony whereof, We have signed our 5 taining oxidizing agent. namesto this specification this 6th day of 15 4. The method of bleaching furskins and Oct, 1925. the like, which comprises brushing the same With anaqueous solution of hydrogen per- HYMAN STEIN. oxide containing ammoniaand a water-solu- WILLIAM E. AUSTIN. 1o ble soap, and thereafter causingthe fur skin IRVING LIEBOWITZ.

